The present invention relates to a novel oxide sintered product and, more particularly, to a sintered product the electric resistance of which changes with a change in temperature with a negative temperature coefficient. Such sintered product can be used for temperature measurement, temperature compensation, etc., as a thermistor, for example.
Conventionally, Mn-Ni-Co type oxide sintered products, etc., have been known as thermistors for temperature measurement.
With such thermistors, however, the crystal structure changes in the vicinity of a temperature of 300.degree. C. and the characteristics as a thermistor are lost as a result of the change, hence the upper limit of usable temperature was as low as 300.degree. C.
For this reason, recently several thermistors such as those comprising a Zr type oxide sintered product, etc., have been developed as thermistors for measuring high temperatures. Such thermistors however show a high electric resistance below 700.degree. C. so that they cannot be used for general purpose circuits.
The invention has been made in view of the conventional technical problems mentioned above. The purpose of the invention is to provide an oxide sintered product usable as a thermistor capable of continuously measuring the temperature from room temperature to 700.degree. C. or so.
As a result of diligent investigations for solving said problems, the inventors have found a novel oxide sintered product, leading to the completion of the invention.